Laser Excited Fluorescence Spectra of Gaseous Te2

1975 ◽  
Vol 53 (19) ◽  
pp. 1976-1982 ◽  
Author(s):  
T. J. Stone ◽  
R. F. Barrow
Keyword(s):  
Ground State ◽  
Fluorescence Spectra ◽  
Single Mode ◽  
Laser Fluorescence ◽  
Fixed Frequency ◽  
Moderate Resolution ◽  
Ion Laser ◽  
Argon Ion ◽  
Emission Studies ◽  
Laser Fluorescence Spectroscopy

Three lines of the argon ion laser have been used to excite spectra of 128Te2 and 130Te2 which have been photographed with moderate resolution (up to about 300 000). Excitation is critically dependent on the operation of the laser as between multimode or single mode. The development of rotational structure can be varied by control of the pressure of Te2. In addition to the systems A 0u+, B 0u+–X 0g+, well known in the absorption spectrum, four series assigned to B 0u+–X 1g have been analyzed and a new system ascribed to B 1u±–X 1g± has been discovered. Constants (in cm−1) for the ground state of 130Te2 are as follows:[Formula: see text]It is concluded that laser fluorescence spectroscopy, even with fixed frequency lasers, has some advantages over conventional absorption and emission studies.

Characteristics of polymeric optical passive single-mode waveguiding devices fabricated by an argon-ion laser

1998 ◽  
Vol 37 (28) ◽  
pp. 6779 ◽  
Author(s):  
Alok K. Das ◽  
Bharat S. Chaudhari ◽  
Shila Ghosh
Keyword(s):  
Single Mode ◽  
Argon Ion Laser ◽  
Ion Laser ◽  
Argon Ion

Laser-fluorescence experiments with a continuous argon-ion laser in an argon plasma

1988 ◽  
Vol 40 (2) ◽  
pp. 135-141 ◽  
Author(s):  
K. Yuasa ◽  
H.M.J. Willems ◽  
B. van der Sijde ◽  
D.C. Schram
Keyword(s):  
Argon Plasma ◽  
Laser Fluorescence ◽  
Argon Ion Laser ◽  
Ion Laser ◽  
Argon Ion

The Development of a Doppler Global Velocimeter for Transonic Turbine Applications

1994 ◽  
Author(s):  
Roger W. Ainsworth ◽  
Steven J. Thorpe
Keyword(s):  
Continuous Wave ◽  
Ccd Camera ◽  
Single Mode ◽  
Rotating Disc ◽  
Iodine Cell ◽  
Ion Laser ◽  
Transonic Turbine ◽  
Argon Ion ◽  
Frame Grabber

The development of a Doppler Global Velocimeter (DGV) for the measurement of transonic turbo-machinery flows in the Oxford Isentropic Light Piston Tunnel rotor facility is described. A novel optical arrangement for capturing both reference and iodine cell discriminated images with a single CCD camera and frame grabber is presented. Practical arrangements for determination of the iodine cell transmission properties as a function of temperature and light frequency are discussed in the context of using an argon ion continuous wave laser for illumination. Flow seeding aspects of the experiment are described with particular emphasis on particle dynamics and light scattering. Error bounds for the DGV measurements are assessed and quantified in respect to the frame grabber resolution and Gaussian beam profile. Results of measurements of the velocity of a rotating disc with tip speed of nominally 90 m/s, obtained with 0.5 W single mode argon ion laser illumination are presented. Practical aspects for employing the DGV on the established Oxford rotor facility, such as seeding of the flow, optical access and synchronisation of data acquisition are addressed.

Single-mode laser fluorescence of NO2 excited at 488 nm

1981 ◽  
Vol 59 (4) ◽  
pp. 559-566 ◽  
Author(s):  
M. J. Armstrong ◽  
J. C. D. Brand ◽  
C. di Lauro
Keyword(s):  
Intensity Distribution ◽  
Ground State ◽  
Cavity Mode ◽  
Single Mode ◽  
Laser Fluorescence ◽  
Mode Laser ◽  
Single Mode Laser ◽  
Vibrational Levels ◽  
Single Cavity ◽  
Single Cavity Mode

The 488 nm line of the Ar+ laser operated in a single cavity mode excites absorption–fluorescence cycles in which an unusually high proportion exhibit anomalies in the selection rules, including transitions to a1 vibrational levels with values of ΔK = Kinitial – Kfinal of 4,2,0, and −2. Many transitions in the fluorescence, especially the weaker bands, show an intensity distribution different from that expected for type A bands of a 2B2–2A1 transition; this is attributed to interference between the dominant μa moment and a secondary, perpendicular transition moment considered to result from a perturbation of the intermediate state of the cycle by the 2B1 state.Data from about 20 fluorescence bands are used to determine the coefficient of a sextic anharmonic resonance, ν1ν2ν3, ν1, − 3, ν2 + 1, ν3 + 2 in the ground state of NO2.

scholarly journals Diffusion coefficient of fluorescein-labeled tubulin in the cytoplasm of embryonic cells of a sea urchin: video image analysis of fluorescence redistribution after photobleaching.

1984 ◽  
Vol 99 (6) ◽  
pp. 2157-2164 ◽  
Author(s):  
E D Salmon ◽  
W M Saxton ◽  
R J Leslie ◽  
M L Karow ◽  
J R McIntosh
Keyword(s):  
Diffusion Coefficient ◽  
Sea Urchin ◽  
Video Camera ◽  
Laser Fluorescence ◽  
Lytechinus Variegatus ◽  
Embryonic Cells ◽  
Ion Laser ◽  
Argon Ion ◽  
Brain Tubulin ◽  
Small Oligomer

The diffusion coefficient of tubulin has been measured in the cytoplasm of eggs and embryos of the sea urchin Lytechinus variegatus. We have used brain tubulin, conjugated to dichlorotriazinyl-aminofluorescein, to inject eggs and embryos. The resulting distributions of fluorescence were perturbed by bleaching with a microbeam of light from the 488-nm line of an argon ion laser. Fluorescence redistribution after photobleaching was monitored with a sensitive video camera and photography of the television-generated image. With standard photometric methods, we have calibrated this recording system and measured the rates of fluorescence redistribution for tubulin, conjugated to dichlorotriazinyl-aminofluorescein, not incorporated into the mitotic spindle. The diffusion coefficient (D) was calculated from these data using Fick's second law of diffusion and a digital method for analysis of the photometric curves. We have tested our method by determining D for bovine serum albumin (BSA) under conditions where the value is already known and by measuring D for fluorescein-labeled BSA in sea urchin eggs with a standard apparatus for monitoring fluorescence redistribution after photobleaching. The values agree to within experimental error. Dcytoplasmtubulin = 5.9 +/- 2.2 X 10(-8) cm2/s; DcytoplasmBSA = 8.6 +/- 2.0 X 10(-8) cm2/s. Because DH2OBSA = 68 X 10(-8) cm2/s, these data suggest that the viscosity of sea urchin cytoplasm for protein is about eight times that of water and that most of the tubulin of the sea urchin cytoplasm exists as a dimer or small oligomer, which is unbound to structures that would impede its diffusion. Values and limitations of our method are discussed, and we draw attention to both the variations in D for single proteins in different cells and the importance of D for the upper limit to the rates of polymerization reactions.

The ground state of Na2

1989 ◽  
Vol 67 (9) ◽  
pp. 912-918 ◽  
Author(s):  
O. Babaky ◽  
K. Hussein
Keyword(s):  
Fourier Transform ◽  
Gas Phase ◽  
Ground State ◽  
Laser Induced Fluorescence ◽  
Rotational Relaxation ◽  
Fixed Frequency ◽  
Molecular Constants ◽  
Vibrational Levels ◽  
Laser Frequencies ◽  
Ion Laser

The laser-induced fluorescence of the [Formula: see text] and [Formula: see text] transitions of Na2 are analysed, using high resolution Fourier transform spectroscopy. Fixed-frequency ion-laser lines (4880 and 4765 Å (1 Å = 10−10 m) from Ar+ and 6471 and 4762 Å from Kr+) together with laser frequencies from a ring dye laser, using rhodamine 6 G with λ = 5781.22 and 5796.80 Å, were used to excite Na dimer in the gas phase. Twenty-eight series of [Formula: see text] and [Formula: see text] systems have been assigned and analysed, and the strong transitions are accompanied by numerous rotational relaxation lines. Molecular constants of the [Formula: see text] state were calculated with high precision from simultaneous least-squares fits to 1410 lines assigned to the A–X and B–X systems. These constants have been used to determine the Rydberg–Klein–Rees potential curve of the X ground state for vibrational levels up to ν = 62.

Wear-Induced Changes in the Raman, Infrared, and Fluorescence Spectra of Silicon Nitride Surfaces

1996 ◽  
Vol 50 (11) ◽  
pp. 1378-1388 ◽  
Author(s):  
James L. Lauer
Keyword(s):  
Silicon Nitride ◽  
Fluorescence Spectra ◽  
Wear Track ◽  
Laser Excitation ◽  
Energy Gap ◽  
Silicon Oxycarbide ◽  
Ion Laser ◽  
Argon Stream ◽  
Induced Changes ◽  
Argon Ion

Commercial α-silicon nitride plates and balls used in simulated sliding bearing tests were found to fluoresce under 514.5-nm argon-ion laser excitation after heating to above 350 °C in a stream of argon. Wear track areas fluoresced much more intensely than their surroundings. When small concentrations of ethylene or other carbonaceous gas were added to the argon stream, carbonaceous deposits formed primarily in the wear track in amounts roughly paralleling the fluorescence intensity. Some of the deposits were lubricating carbon and some nonlubricating silicon oxycarbide. Continuous high-temperature lubrication was possible by balancing deposit removal by wear with surface-chemical deposit formation rates. Raman, infrared, fluorescence, and other spectroscopies helped explain the process. Defect energy states within the large silicon nitride energy gap and dangling bonds appear to play a role.

Sign in / Sign up

Export Citation Format

Share Document